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1.
杜芳彦  周媛 《光谱实验室》2001,18(3):385-387
提出了用火焰原子吸收光谱法测定高铝锌基合金中镁的方法,在测定条件下,共存元素的干扰可消除,能测定高铝锌基金合中0.001-0.01%,范围内的镁,该方法相对标准偏差<6%,样品加标回收率为94-102%。  相似文献   

2.
火焰原子吸收光谱法连续测定茶叶中的锌、铜和锰   总被引:16,自引:0,他引:16  
本文研究了茶叶中锌、铜、锰微量金属元素的火焰原子吸收分光光度法的测定。方法简便、快速,灵敏度和精密度高,特征浓度锌为0.009μg/mL/1%,铜为0.031μg/mL/1%,锰为0.017μg/mL/1%;相对标准偏差为0.9%~5.0%,回收率92.0%~106.0%。  相似文献   

3.
本文用火焰原子吸收光谱法研究测定了人(肺结核、肺癌)胸水中铜、锌、铁。测定肺结核胸水21例,该胸水中铜、锌、铁含量平均值分别为0.71±0.08mg/L,4.78±0.18mg/L,3.22±0.15mg/L。肺癌胸水21例,其胸水铜、锌、铁含量为0.98±0.09mg/L,3.80±0.16mg/L,5.35±0.21mg/L。该方法的回收率为95.21%-105.54%。相对标准偏差小于4.84%。  相似文献   

4.
火焰原子吸收光谱法测定淋巴液中铜锌铁钙镁   总被引:2,自引:0,他引:2  
本文研究了淋巴液中铜、锌、铁、钙、镁微量金属元素的火焰原子吸收光谱法的测定。采用湿法消化法处理样品,方法简便、快速,铜、锌、铁、钙、镁的样品加标回收率分别为99.2%、103.0%、102.0%、104.0%和98.5%。  相似文献   

5.
火焰原子吸收法测定前列腺液中锌、铜、锰   总被引:1,自引:0,他引:1  
陈烈 《光谱实验室》1999,16(2):154-156
用火焰原子吸收光谱法测定了健康成年男性及慢性前腺炎患者的前列腺液中微量元素锌,铜,锰,确定三种元素最佳仪器工作条件,对共存元素的干扰情况进行了研究。该方法简便,快速,准确,相对标准偏差在2.5%以内,回收率为96.0%-102.0%。  相似文献   

6.
原子吸收法测定人精子中锌和铜含量的研究   总被引:1,自引:0,他引:1  
本文采用石墨炉原子吸收法,以NH4NO3和Mg(NO3)2混合剂作基体改进剂,测定了人精子中微量元素铜和锌。基方法的特征质量分别为10.00pgCu/0.0044A.S.,9.80PgZ/0.004A.S;平均加收率为97.42%,锌为101.91%,铜和锌的精密度分别是4.1%和4.03%。  相似文献   

7.
叙述了镧-镍-铝(La-Ni-Al)合金分镍、铝及微量杂质元素锌、铁、锰、镁、硅、铜和钙的ICP-AES测定方法。样品以HNO3(1+1)溶解,稀释后直接测定主量元素镍和铝;用基体匹配法补偿基体效应测定其他杂质元素。各元素回收率在95%-106%,相对标准偏差优于5%。  相似文献   

8.
用电感耦合等离子体质谱(ICP-MS)对鲨鱼有进行全元素的半定量分析。用电感耦合等离子体原子发射光谱(ICP-AES)对其进行微量元素测定,选用钇作内标元素,可较好地克服基体效应,所研究元素的回民率在81.6-100.7%之间,铁、锌、硒、铜、锰、钼,钛和锶等元素的测定下限分别是:0.60、0.55,0.21,0.39,0.042,0.27,0.038,0.48μg.g^-1,实验表明鲨鱼软骨含有  相似文献   

9.
ICP-AES测定铝锭中八种杂质元素   总被引:2,自引:0,他引:2  
本文研究了名对铁、锰、铜、锌、镁、钛、硅、镓等分析元素的干扰情况,采用了基体匹配法进行基体干扰校正,采用干扰系数法扣除杂质元素间光谱干扰引起的分析偏差,从而确定了铝锭中八种杂质元素同时测定的最佳工作条件,并用实际样品把本方法与化学法的测定进行对比,结果令人满意。方法回收率在92.9%-105%之间,精密度在0.82%-2.32%之间,该方法快速、简便、可靠,适用于进出口铝锭的日常检验。  相似文献   

10.
本文采用硝酸溶解试样,制成试样浓度为0.5-1mg/mL,盐酸浓度为10%(V/V)的溶液,ICP-AES法直接测定铜稀土含金中0.05% ̄10%的单一稀土元素。研究了铜基体及其他元素干扰,选择了合适的分析线,优化了测定条件。方法准确,简单,快速,已用于铜稀土合金研究中的样品分析。  相似文献   

11.
Cyclic competition game models, particularly the “rock–paper–scissors” model, play important roles in exploring the problem of multi-species coexistence in spatially ecological systems. We propose an extended “rock–paper–scissors” game to model cyclic interactions among five species, and find that two of the five can coexistent when biodiversity disappears, which is different from the “rock–paper–scissors” game. As the number of fingers is five, we named the new model the “fingers” game, where the thumb, forefinger, middle finger, ring finger, and little finger cyclically dominate their subsequent species and are dominated by their former species. We investigate the “fingers” model in two ways: direct simulations and nonlinear partial differential equations. An important finding is that the number of species in a cyclic competition game has an influence on the emergence of biodiversity. To be specific, the “rock–paper–scissors” model is in favor of maintaining biodiversity in comparison with the “fingers” model when the variables (population size, reproduction rate, selection rate, and migration rate) are the same. It is also shown that the mobility and reproduction rate can promote or jeopardize biodiversity.  相似文献   

12.
The differences of the pitch and duration of Chinese syllables between Putonghua (PTH) and Taiwan Mandarin (TM) were studied. The speech materials to be used are not only isolated syllables, but also sentences. The results reveal that: For the isolated syllables, T1 and T2 in TM are influenced by Minnan dialect, therefore their pitch are lower than those in PTH. T3 is fall-rise in PTH, while it is fall in TM. Moreover, the syllable duration sequence for different tone is T3〉T2〉T1〉T4 in PTH, while it is T1〉T2〉T3〉T4 in TM. For the syllables in sentences, T2 is mid-rise in PTH, while it is mid-level in TM. And the T3 is longer than T4 but shorter than T1 or T2 in PTH, while it is the shortest in TM. Furthermore the effects of prosodic phrase boundary on duration for different tones are almost the same in PTH, but the lengthening part of T1 or T2 is longer than that of T3 or T4 in TM.  相似文献   

13.
Downstep in pitch contour of Chinese Putonghua is examined using subtly designed sentences by controlling tone combinations. The results show both automatic and nonautomatic downstep phenomena exist in Chinese. In non-automatic downstep, low tones compress downwards the pitch range of the following syllables. and the main influence of downstep is on topline. Low tone not only lower the topline behind it, but also raise the high tones before it, the effects are compatible with each other. In automatic downstep, the topline of pitch contour in intonational phrase is presented as a linear downtrend, but it differs among speakers due to the effect of personal stress practice. In comparison with downstep phenomenon in other tone or non-tone languages, the downstep ratio in Chinese is not constant, and the domain of downstep is not limited within the adjacent tones.  相似文献   

14.
It is shown that SU(2) QCD admits an dual Abelian-Higgs phase, with a Higgs vacuum of a type-Ⅱ superconductor. This is done by using a connection decomposition for the gluon field and the random-direction approximation. Using a bag picture with soft wall, we presented a calculational procedure for the glueball energy based on the recent proof for wall-vortices [Nucl. Phys. B 741(2006)1].  相似文献   

15.
16.
A multi-conjugate adaptive optics (MCAO) can offer a possibility of widening field of view (FOV) characterized by the isoplanatic angle, and the choose of conjugate height becomes a basic problem for MCAO, which influences the size of iosplanatic angle. Considering the application of lidar, the isoplanatic angle's expressions of two deformable mirrors (DMs) MCAO for uplink and downlink are deduced. The effects of conjugate heights for dual-conjugate AO are thoughtfully discussed, and the isoplanatic angles are further analyzed. The results show that the isopanatic angle varies with the conjugate height and reaches the maximum as the conjugate height is at the optimal altitude. Moreover, the optimal conjugate height changes with the propagation distance.  相似文献   

17.
Due to the limit of response speed of the present single-photon detector, the code rate is still too low to come into practical use for the present quantum key distribution (QKD) system.A new idea is put up to design a quick single-photon detector.This quick single-photon detector is composed of a multi-port optic-fiber splitter and many avalanche photo diodes (APDs).Au of the ports with APDs work on the time division and cooperate with a logic discriminating and deciding unit driven by the clock signal.The operation frequency lies on the number N of ports, and can reach N times of the conventional single-photon detector.The single-photon prompt detection can come true for high repetition-rate pulses.The applying of this detector will largely raise the code rate of the QKD, and boost the commercial use.  相似文献   

18.
19.
Based on the research in Ref. [5][Materials Science and Engineering, 1989; A122: 57 63], an improved model of heat source is set up, the different modes of Lamb wave in an isotropic sample generated by a chopped electron beam at frequency f are obtained with integral transform and normal function expansion method, and the output signal of PZT coupled at the back surface of the sample is found out. The generation mechanism of SEAM (Scanning Electron Acoustic Microscopy) signal is discussed. It shows that the SEAM is a near field imaging technique with high spatial resolution and its best lateral spatial resolution is about 2√2α (α is the radius of the focused electron beam). Some of experimental results of SEAM images are presented in the paper and it shows that the spatial resolution of SEAM is better than 0.5 μm and smaller than the thermal diffusion length of the sample. Therefore the character of near field imaging in SEAM is also proved experimentally.  相似文献   

20.
Transmission spectra of coupled cavity structures (CCSs) in two-dimensional (2D) photonic crystals (PCs) are investigated using a coupled mode theory, and an optical filter based on CCS is proposed. The performance of the filter is investigated using finite-difference time-domain (FDTD) method, and the results show that within a very short coupling distance of about 3λ, where λ is the wavelength of signal in vacuum, the incident signals with different frequencies are separated into different channels with a contrast ratio of 20 dB. The advantages of this kind of filter are small size and easily tunable operation frequencies.  相似文献   

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